Electromagnetic switch.



No. 768,549. PATENTED AUG. 23, 1904. s. B. STEWART, JR.

ELECTROMAGNETIC SWITCH.

APPLICATION FILED FEB. 14, 1903.

NO MODEL.

WITNESSES. INVENTOR. M Samuel BSCevartJr. 4% (Qq/fm L by v AEEy UNITEDSTATES Patented August 23, 1 9 04.

PA TENT OFFI E.

SAMUEL n. sirmvART, JR, or sc'nENEorADy. NEW YORK, ASSTGNOR TO GENERALELEe'rmc COMPANY, A CORPORATION OF NEW YORK.

ELECTROMAGNETIC SWITCH.

smacrnea'non forming part of Letters Patent No. 768,549, dated August23, 1904.

Original application lilod Kay 2O, 19% Serial No. 108,288. Divided unithil application filed February 14, 1903. Burial In.

- 143,319. (No modQL) T n all urlumr it 11mg, concern.-

lie it known that 1.,SAMUEL Esme. n'rgJ r.. a citizen of the UnitedStates. residing at Schenectady, county of Schenectady. State of New 5York havc invented certain new and nsefui Improvements in lllectrommeticSwitches, of which the following is a specification.

My invention relates to electromagncticallyactuated switches,- andespecially tosuch switches as are adapted for use in sectionalconductorclectric-railway '5iC! S such, for instancmas that illustrated anddescribed in my application Serial No. 105.283, filed May 20, 1902, ofwhich the present case is a division.

The object of my invention is to provide a switchof such constructionthatit will handle heavy currents in a quick and eflicie'nt manner andwith much less injury-to the working parts of the switch than ispossible with the switches at present in use.

In the accompanying drawings, which represent the prefe rred embodimentof my invention,

Figure 1 is a vertical section of the =5 switch on the line 1 1 of Fig.2. Fig. 2 is a side elevation of the switch, and Fig. 3 is a plan viewshowing the relative position of the switch-actuating coil and theblow-out magnetcoilsv Referring now to the figures of the drawings, 7;represents an insulating-base which carries the switch andswitch-actuating mechanism. .The base '11 may be made of slate, pressedfiber, or other insulating material. A

casing D, of magnetic material, is provided with a cover E, which has aportion F extendingas a stationary core into a non-magnetic spool g, onwhich an energizing coil or solenoid H is wound. The leads to said coilare indicated at 4 12 and 13. The stationary core F (shown in Fig. 1) isseparable from the-cover E; but it may be formed integral therewith. Thesolenoid-core K carries at its lower end, which 4 projects through anopeningin the caseb, a switch or contact-brush S, which engages with thecontacts (I, of conducting material, secured to the under side of thebase'b. The switch S is preferably made of laminated copper strips,

which are mounted in the block h,which is fw tened to the core K by thebolt 6'. integral with the block ii are the lugs l which act as bearingsfor theshafts p. on which the hell-crank levers n. n' are mounted. Theauxiliary contacts a, which also engage with the fixed contacts d,areremovably mounted on the 5 ends 11 of the bell-crank n n. The arms n arenormally spread apart by the spring 6 and are electrically connectedtogether by the conducting-band w. This construction permits theauxiliary contacts 0' to engage the fixed conmts (Z with a slidingacti'omwhich is transverse to the-direction of the movement of approachof said auxiliary contacts, thereby obtaining a betterelectrical contactthan would I otherwise be obtained, and also permitting the' contacts cto leave the contacts (Z later than the switch S, and thereby form asecondary break. Therefore the only parts liable to injury by arcingwhen heavy currents are 1 in this type-of switch. are the auxiliary con-7:; tacts c', which are made replaceable for this reason. To reduce theinjury due to arcing at the contacts the blow-out magnets M areprovided, one for each contact-block The magnetic circuit of one ofthese magnets may be traced on Fig. 2, in which 2 represents the core ofthe magnet, 3 3' pieces for supporting the core above the base I), and5,.5' the poles below the base 6, between which poles one of thecontacts (1 is mounted. The magnet-poles and core-supporting pieces areheld in place by means of bolts 4 4', which pass through the base 6 andform part of the magnetic circuit. On either side of each of I thecontact-blocks d are strips of insulating material 0, which depend fromsaid base 6 at right angles thereto and form chutes along which the arcsformed when the switch is opened are blown. The electrical circuit foreach of the blow-out magnets may be traced 9:

as follows, (see Fig.3:) The terminal 0 is connected tothe angle-piece uby means of the bolt r, which passes through the base 6, the currentflowing from said terminal through the. bolt 7-, angle-piece u, coil m,angle-piece u, bolt '1", whith connects angle-piece u to Formed 5o oneof the fixed contacts (I on the under side of the base I, through thecontact-switch S and the'auxiliary switch to the other contact (Ithrough bolt 1'. which connects the anglemounted on the shaft gfandconnected there- .withthrough the springs s'are the semaphorearms a,carrying the disks s. The semaphorea'rms s are in a horizontal positionwhen the switch is open, but are raised to a vertical position, as shownin Figs. 1 and 2, when the switch is closed. A spring 72,, against whichthe head w'strikes in its downward movement, is provided in a recess inthe fixed core F for the purpose ofireducing the shock tothe apparatuswhen the'switch opens.- The semaphore-disks act rm signals to indicatethe condition of the switch, and when said switch is used insectional-conductor electric railways the semaphores serve to indicatewhether the sectional third rail is energized or not. 'The specific formof sem'aphore-signalherein shown is notclaimed in this application,since it forms the subject-matter of my application above referred to.

When the switch-actuatingcoilbecomes de- V energized, the switch Sopensby gravity and the arcs which occasionally form between theauxiliary contactsc' and the fixed contacts (I are projected by theblow-out magnets M along the chute formed by the insulatingg-uides o.

\Vhat I claim as new, and desire to secure by Letters Patent of theUnited States, is

1. In a switch, a solenoid mounted on mainsulating-base, the core ofsaid solenoid passing through an opening in said base, fixedswitch-contacts attached to the under side of said base, a movableswitch element comprising a main contact-maker of laminatedconducting-strips, and an auxiliaryspring-pressed contact-makercarriedbysaid core at its lower end and adapted to make a sliding engagementwith said fixed contacts, the said auxiliary contact-maker beingarranged to 'engage the fixed contacts prior to and leave said contactslater than the main coritact-maker.

2. In a switch, a solenoid'mounted on an insulating-base, the core ofsaid solenoid passing through an opening in said base, fixedswitch-contacts attached to the under side of said base, a movableswitchelement comprisduct ing-stri psi and a n auxiliary springmressedcontact-maker carried by said core at its lower end and adapted toengage said fixed contacts,

the said auxiliary contact-maltcr being arranged to engage said fixedcontacts prior to and to leave said fixed'ccntacts later than the maincontact-maker, and a blow-out magnet for each fixed contact having itspoles arrange o embrace said contact and its-coil mounted oz:- the upperside of said 1 ise.

, 3. In an electromagnetic switch, a solenoid,

fixed contacts with which said contact-makers are adapted to engage,said auxiliary contactmaker comprising electrically connectedspring-pressed arms pivoted to said core in such a manner as to allowsaid auxiliar con.- tact maker to engage the relatively fixed contactswith a sliding action.

4. In an electromagnetic switch, a solenoid, a core for said -solenoidcarrying main and auxiliary contact-makers adapted to engage fixedcontacts, a blow-out magnet for each fixed contact having its polesembracing said fixed contacts, and ijsulatingchutes along which the arcswhich tcndto form between the movable contact-makers and the fixedcontacts are projected by the blow-out magnets.

5. In an electromagnetic switch, a solenoid mounted on aninsulating-base, a core for said solenoid passing through an opening insaid base, fixed switch-contacts attached to the under side of saidbase, a movable switch-element carrying contactmakers adapted to engagesaid fixed contacts,- and a blow out magnet for each fixed contact thepoles of which are adapted to embrace said fixed contact.

6. In an electromagnetically actuated switch, a solenoid mounted on aninsulating- :00

base, the core of said solenoid passing through an opening in said base,fixed switch-contacts attached to the under side of said base, a movableswitch element comprising contactmakers carried by said core at itslower end 5 magnetic poles adapted to embrace the said no fixed contactson the under side of said base. In witness whereof I have hereunto setmy hand this 12th day of February, 1903.

SAMUEL B. STEWART, JR.

\V-itnesses:

BENJAMIN B. HULL, HELEN Oman.

